The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 02, 2014
Filed:
Sep. 06, 2011
Hideyasu Seki, Tokyo, JP;
Yasuyuki Ishii, Tokyo, JP;
Hideki Kosugi, Kanagawa, JP;
Tetsuro Hirota, Kanagawa, JP;
Masaaki Yamada, Tokyo, JP;
Atsushi Kurokawa, Kanagawa, JP;
Hideyasu Seki, Tokyo, JP;
Yasuyuki Ishii, Tokyo, JP;
Hideki Kosugi, Kanagawa, JP;
Tetsuro Hirota, Kanagawa, JP;
Masaaki Yamada, Tokyo, JP;
Atsushi Kurokawa, Kanagawa, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
A development device includes a developer container; a rotary cylindrical developer carrier including an outer electrode including multiple electrode portions arranged in a circumferential direction of the developer carrier, an inner electrode provided on an inner circumferential side of the developer carrier from the outer electrode, an insulation layer disposed between the outer electrode and the inner electrode, and a surface layer; and a bias power source to apply a first bias voltage and a second bias voltage to the inner electrode and the outer electrode, respectively. The first bias power source causes an electrical potential difference that changes with time between the inner electrode and the outer electrode to cause the developer to hop on a circumferential surface of the developer carrier. At least one of the first bias voltage and the second bias voltage has a cyclic waveform in which pulse-on time is reduced.